Hot Isostatic Pressing (HIP) processes are often utilized to produce Powdered Metal (PM) articles or components. During an exemplary HIP process, a PM alloy is loaded into the cavity of a specialized capsule or “HIP container.” The HIP container is then subject to elevated temperatures and isostatic pressures sufficient to consolidate or sinter the PM alloy into a coherent mass or “component preform,” which may have the near net shape of the finished component. After HIP processing, the component preform is removed from the HIP container and subjected to additional machining to define the more detailed features of the finished PM component. HIP processes of this type are employed across a wide range of industries to produce a number of different PM components. The aerospace industry, for example, has developed HIP processes suitable for producing Gas Turbine Engine (GTE) components including compressor rotors and turbine rotors (collectively referred to herein as “GTE rotors”). In certain instances, it may be desirable to produce shaped cavities within a PM component for a particular purpose. For example, in the case of a GTE rotor, it may be desirable to produce shaped cavities within the rotor hub for cooling or stress relief purposes. This can present a difficultly, however, in that such shaped cavities may have portions or regions that are not accessible from the exterior of the PM component and/or that have relatively complex three dimensional geometries. As a result, it can be impractical, if not impossible to produce such shaped cavities utilizing conventional machining techniques.